Earlwb,
A baffled engine will respond to a tuned pipe just fine. Just like a schnuerle ported engine the greater the blow down period the stronger the pipe response.

Now with a baffle engine it is a little harder to control detonation as the baffle does destroy smooth flame propagation across the piston. This smooth piston top is the real reason that the schnuerle ported engine can develop more power than its PDP brethren.

All the best,

Konrad